In 1941 he underwent a serious operation.

在1941年，他经历了严重的作业。

youdao

During the process, strict management and serious operation resulted in good effects.

在施工过程中，严格管理，认真操作，取得较好的施工效果。

youdao

We never dreamt that old Tom would still be kicking around after such a serious operation.

我们做梦也没想到，在经历了这样一次大手术以后，老汤姆还能健康地活着。

youdao

He is currently convalescing from a recent serious operation and is unable to conduct any further interviews.

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When my loved one is undergoing a serious operation as I pace in the waiting room, the surgeon is under pressure while I am under stress.

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Already, it would be hard for the Europeans to mount a serious military operation without American help.

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